A rut-free pavement asphalt modifier, its preparation method and application

Abstract

The application discloses a rut-free pavement asphalt modifier, a preparation method and application thereof. The rut-free pavement asphalt modifier is obtained by mixing mixture A and mixture B, wherein the mixture A is obtained by blending and modifying synthetic powder rubber, rubber filling oil and solid phenolic epoxy resin by using a special grinding disc-shaped force chemical reactor, and the mixture B is obtained by grinding long-chain fatty amine, carbon black, sulfur, accelerant, antioxidant and ultraviolet absorbent by using a plastic grinder, and the rut-free asphalt mixture is prepared by using the rut-free pavement asphalt modifier. The rut-free asphalt mixture can greatly improve high-temperature rut resistance and low-temperature crack resistance, and can be widely applied to long-life paving of various-grade highway asphalt pavement, bridge surface and tunnel, and is especially suitable for road sections prone to serious rutting under the action of heavy traffic and creep load for a long time.

Description

Technical Field

[0001] This invention relates to the field of road engineering, and more particularly to a rutting-free asphalt modifier for use in rutting-resistant pavements under heavy traffic, its preparation method, and its application. Background Technology

[0002] With the rapid development of the national economy, my country's transportation volume has been continuously increasing. Serious vehicle overloading, traffic channelization, the rapid increase in vehicle size, and persistent high temperatures, coupled with deficiencies in later-stage highway management, have led to severe early damage to many high-grade highways, such as spalling and rutting. Among early pavement distresses, rutting is a unique form of damage to asphalt concrete pavements. Especially under high temperature and heavy load conditions, areas where vehicles concentrate their longitudinal passage along the asphalt road are prone to developing strip-shaped grooves, forming rutting distress. As vehicle loads continue to increase, bulging deformation appears on both sides of the ruts, seriously affecting the quality of road use. In recent years, the rutting resistance of pavements has been improved by adding anti-rutting agents and high-modulus agents. However, there are many types of anti-rutting agents and high modulus agents on the market. Most of them use waste plastics PE, PP and hard asphalt as the main materials. They improve the rutting resistance of asphalt mixtures by increasing the viscosity and stiffness modulus of asphalt. However, their anti-rutting effect is limited on severely rutted road sections subjected to heavy traffic and creep loads for a long time (such as truck congestion sections at ports and wharves, intersections of national and provincial highways with heavy traffic, bus bays, etc.). In addition, anti-rutting agents and high modulus agents have a certain negative impact on the low-temperature crack resistance of asphalt mixtures.

[0003] Currently, grouting composite pavement is used for the aforementioned severely rutted road sections. This involves first laying a large-void asphalt mixture, then injecting high-strength cement grout. The strength of the cement grout improves the pavement's resistance to rutting. However, this method is complex (laying the mixture first, then grouting), requires specialized equipment, and is costly (30-40 yuan / m²). 2 The asphalt mixture suffers from problems such as cracking due to its high epoxy content ( / cm) and the tendency of cement materials to crack. In recent years, the introduction of epoxy thermosetting materials into asphalt mixtures has significantly improved their performance. For example, CN110713695A (an ultra-high toughness epoxy resin material for hot-mix epoxy asphalt and its preparation method) and CN111875930A (a hot-mix epoxy resin, its preparation method, and its uses) use modified epoxy resins to prepare epoxy asphalt mixtures with excellent rutting resistance. However, epoxy asphalt mixtures require a large epoxy content, resulting in high costs (4500-5500 yuan / ton, compared to 500-600 yuan / ton for ordinary asphalt mixtures), difficult construction, low early strength, and long curing time (around 7-40 days), making them unsuitable for maintenance projects. They are generally only used in special applications such as steel bridge decks and tunnels, hindering large-scale application.

[0004] Given the lack of effective solutions to the severe rutting problem in existing road sections subjected to heavy traffic and creep loads over extended periods, the high difficulty and cost of constructing grouting pavements and epoxy asphalt mixtures, and the long curing time of epoxy asphalt mixtures making them unsuitable for maintenance projects, this invention addresses these issues. Based on years of extensive practical experience and professional knowledge in the design and manufacture of such products, and through active research and innovation using relevant mechanisms, this invention aims to create a method for preparing and using an asphalt modifier for rutting-free pavements. This method will improve the rutting resistance of asphalt mixtures, reduce construction difficulty and cost, and make them more practical. Summary of the Invention

[0005] The purpose of this invention is to overcome the lack of effective solutions for severe rutting problems in road sections subjected to heavy traffic and creep loads over extended periods, the high difficulty and cost of constructing grouting pavements and epoxy asphalt mixtures, and the long curing time of epoxy asphalt mixtures, making them unsuitable for maintenance projects. Therefore, this invention provides a rutting-free asphalt modifier for pavements, its preparation method, and its application method, making it more practical and possessing industrialization value.

[0006] To achieve the above-mentioned technical objectives, the present invention is implemented through the following technical solution:

[0007] A rutting-free asphalt modifier comprises the following components, with the following mass percentages for each component:

[0008]

[0009] The rutting-free pavement asphalt modifier is obtained by mixing mixture A, which is obtained by blending and modifying synthetic powder rubber, rubber filler oil and solid phenolic epoxy resin using a special disc-shaped mechanical chemical reactor, with mixture B, which is obtained by grinding a mixture of long-chain fatty amine, carbon black, sulfur, accelerator, antioxidant and ultraviolet absorber using a plastic grinding mill.

[0010] Furthermore, the synthetic powder rubber described in this invention is selected from any one of styrene-butadiene rubber (SBR), butadiene rubber (BR), and nitrile rubber (NBR). These synthetic rubber molecules have C=C double bond structures, which can undergo partial epoxy grafting reactions with solid phenolic epoxy resin in a disc-shaped mechanical chemical reactor, thereby improving the compatibility of synthetic powder rubber, phenolic epoxy resin, and asphalt.

[0011] Furthermore, the solid phenolic epoxy resin described in this invention is a solid bisphenol A type phenolic epoxy resin with an epoxy equivalent of 190-210 g / eq and a softening point of 60-70℃. This type of epoxy resin has a high epoxy value, high reactivity, and high functionality. The crosslinking density of the cured epoxy resin is higher than that of conventional E51 epoxy resin cured products, resulting in higher mechanical strength. It can significantly improve the mechanical properties of asphalt mixtures at a lower dosage.

[0012] Furthermore, the rubber filler oil described in this invention is selected from any one of aromatic oil, naphthenic oil, and paraffin oil. The rubber filler oil can improve the fluidity of synthetic rubber during vulcanization production and improve the compatibility between synthetic rubber and asphalt.

[0013] Furthermore, the long-chain fatty amine described in this invention is selected from any one of hexadecylamine, octadecylamine, and oleylamine. These long-chain fatty amines contain flexible C16-C18 chains in their structure, and after curing with epoxy groups, the cured epoxy resin exhibits a certain degree of flexibility.

[0014] Furthermore, the carbon black and sulfur described in this invention serve as reinforcing agents and vulcanizing agents for synthetic rubber, enabling cross-linking vulcanization reactions to occur during the high-temperature production and construction of synthetic rubber, forming a high-strength thermosetting rubber asphalt material and improving the early strength of asphalt mixtures.

[0015] Furthermore, the accelerator described in this invention is a phenolic accelerator, specifically selected from any one of 2,4,6-tris(dimethylaminomethyl)phenol, nonylphenol, and phenol. The accelerator can accelerate the curing reaction rate between the phenolic epoxy resin and the curing agent.

[0016] Furthermore, the antioxidant described in this invention is selected from any one of antioxidant BHT, antioxidant 1010, and antioxidant 264. The antioxidant can reduce the aging of synthetic rubber during high-temperature mixing and construction.

[0017] Furthermore, the ultraviolet absorber described in this invention is selected from any one of ultraviolet absorbers UV-531, UV-326, and UV-329. The ultraviolet absorber reduces the absorption rate of ultraviolet rays by the modified asphalt material when used on the road surface, improves the material's resistance to ultraviolet aging, and extends the service life of the road surface.

[0018] The preparation process of the rutting-free pavement asphalt modifier of the present invention is as follows:

[0019] (1) Weigh the synthetic powder rubber, rubber filler oil and solid phenolic epoxy resin according to the proportion, put them into the mixer and mix them with oil for 3 to 5 minutes. Then add the mixture to the grinding disc mechanical chemical reactor and grind it repeatedly at room temperature. The heat of the grinding process is carried away by cooling water. The grinding is repeated 10 to 30 times to obtain mixture A.

[0020] (2) Add long-chain fatty amines, carbon black, sulfur, accelerators, antioxidants and ultraviolet absorbers to a high-speed mixer in proportion and mix for 2 to 3 minutes. Then add it to a plastic grinding mill and control the grinding fineness to 20-40 mesh to obtain mixture B.

[0021] (3) Add the mixture A prepared in step (1) and the mixture B prepared in step (2) to a flat die granulator for granulation to prepare the rutting-free pavement asphalt modifier of the present invention.

[0022] The rutting-free pavement asphalt modifier described in this invention is applied to asphalt mixtures.

[0023] The present invention also provides a method for preparing rutting-free asphalt mixture using the above-mentioned rutting-free pavement asphalt modifier, comprising the following steps:

[0024] (1) Heat the asphalt and stone separately. Heat the stone to 190-220℃, and heat the asphalt to 150-160℃ when it is base asphalt and to 160-175℃ when it is SBS modified asphalt.

[0025] (2) Heat the mixing pot to 180-190℃, then add the stone material heated in step (1) and the above-mentioned rutless pavement asphalt modifier and dry mix for 10-15 seconds. Mix until the rutless pavement asphalt modifier is completely melted and coated on the surface of the aggregate.

[0026] (3) Add heated asphalt and mineral powder to the mixing pot in step (2), perform wet mixing and molding, the wet mixing time is 45-55s, and discharge to prepare rut-free asphalt mixture. Control the discharge temperature of the mixture to 185-200℃. If the temperature is below 175℃ or above 205℃, it is treated as waste material. The molding temperature of the mixture is 175-185℃.

[0027] In the preparation method of the rutting-free pavement asphalt mixture of the present invention, the dosage of the rutting-free pavement asphalt modifier accounts for 1.0-2.0% of the mass of the aggregate in the mixture, and the aggregate includes stone and mineral powder.

[0028] In the preparation method of rutting-free asphalt mixture of the present invention, the rutting-free asphalt mixture has no special requirements for gradation and is especially suitable for dense-graded asphalt mixtures such as AC, SMA, SUP, and EME.

[0029] In summary, the present invention has the following beneficial effects:

[0030] (1) A special grinding disc-shaped mechanical chemical reactor was used to blend and modify synthetic rubber and phenolic epoxy resin, which improved the compatibility between synthetic rubber, phenolic epoxy resin and asphalt. The thermosetting epoxy resin and vulcanized cross-linked synthetic rubber asphalt formed a three-dimensional inter-transmission network in the asphalt, which improved the high-temperature rutting resistance and low-temperature crack resistance of the asphalt.

[0031] (2) By utilizing the high-temperature conditions during the mixing and construction of asphalt mixtures, the vulcanization reaction of synthetic rubber is achieved, forming a cross-linked high-strength thermosetting rubber material, which improves the strength and elasticity of asphalt mixtures and solves the problem of low early strength of traditional epoxy asphalt mixtures and the need for long-term curing.

[0032] (3) The epoxy resin with high cross-linking degree was toughened and modified by thermosetting synthetic rubber, which improved the low-temperature flexibility and fatigue resistance of epoxy asphalt mixture and improved the fatigue crack resistance of asphalt mixture.

[0033] (4) The asphalt is modified by using two-component bisphenol A phenolic epoxy resin with high functionality. It has a higher crosslinking density and better mechanical properties than traditional bisphenol A epoxy resin. It can improve the mechanical properties of the modified asphalt and can prepare high-performance epoxy asphalt mixtures with low dosage.

[0034] (5) The production process of this invention is simple, the method of using the rutting-free pavement asphalt modifier is simple, it can be directly added during the production of the mixture, it is convenient to use, it adopts conventional hot-mix asphalt construction equipment and construction process, no special equipment is required, and it is highly practical. Detailed Implementation

[0035] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description of the preparation and use method of a rutting-free pavement asphalt modifier according to the present invention, in conjunction with specific embodiments, provides a detailed description of the preparation and use method of a rutting-free pavement asphalt modifier provided by the present invention, but this should not be construed as a limitation on the scope of protection of the present invention.

[0036] The amounts of components used in each embodiment and comparative example are expressed in parts by mass.

[0037] Example 1

[0038] The preparation process of an asphalt modifier for rutting-free pavement is as follows:

[0039] (1) Weigh 300g of synthetic SBR powder rubber, 50g of aromatic oil, and 400g of bisphenol A type solid phenolic epoxy resin into a mixer and mix them with oil for 3 minutes. Then add the mixture to a grinding disc-shaped mechanical chemical reactor and grind it repeatedly at room temperature. Use cooling water to remove the heat during the grinding process. Grind it 10 times to obtain mixture A.

[0040] (2) Weigh out 300g hexadecylamine, 150g carbon black, 5g sulfur, 5g 2,4,6-tris(dimethylaminomethyl)phenol accelerator, 5g antioxidant BHT, and 10g UV-531 ultraviolet absorber respectively, add them to a high-speed mixer for mixing for 2 minutes, and then add them to a plastic grinding mill, controlling the grinding fineness to 20 mesh to obtain mixture B;

[0041] (3) The mixture A prepared in step (1) and the mixture B prepared in step (2) are added to a flat die granulator in a ratio of 1:1 to granulate and prepare a rutting-free pavement asphalt modifier.

[0042] The method for preparing asphalt mixtures using the above-mentioned rutting-free pavement asphalt modifier:

[0043] S1. Use AC-16 gradation for aggregate batching, and heat the base asphalt to 150℃ and the aggregate to 220℃.

[0044] S2. Heat the mixing pot to 180°C, then add the stone material heated in S1 and the rutting-free pavement asphalt modifier and dry mix for 10 seconds. Mix until the rutting-free pavement asphalt modifier is completely melted and coated on the surface of the aggregate. The amount of rutting-free pavement asphalt modifier added is 1% of the aggregate.

[0045] S3. Add heated asphalt and mineral powder to the mixing pot in S2. The asphalt content is added at an asphalt-aggregate ratio of 4.5%. Wet mixing and molding are carried out. The wet mixing time is 45s. The mixture is discharged to prepare a rutting-free asphalt mixture. The discharge temperature of the mixture is controlled at 185℃. The relevant mixture specimens are molded at 175℃. The performance of the mixture is tested according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTGE20-2011). The test results are shown in Table 1.

[0046] Comparative Example 1

[0047] Using AC-16 gradation and imported French PR high-modulus agent, high-modulus AC-16 asphalt mixture was prepared. The preparation method is as follows:

[0048] S1. The base asphalt needs to be heated to 150°C, and the aggregate needs to be heated to 190°C;

[0049] S2. Heat the mixing pot to 180°C, then add the stone material heated in S1 and the PR high modulus agent and dry mix for 10 seconds. Mix until the high modulus agent is completely melted and coated on the surface of the aggregate. The PR high modulus agent is used at 0.7% of the aggregate according to the manufacturer's recommended dosage.

[0050] S3. Add heated asphalt and mineral powder to the mixing pot in S2. The asphalt content is added according to the asphalt-aggregate ratio of 4.8%. Wet mixing and molding are carried out. The wet mixing time is 45s. The PR high modulus asphalt mixture is prepared by discharge. The discharge temperature of the mixture is controlled at 185℃. The relevant mixture specimens are molded at 175℃. The performance of the mixture is tested according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 1.

[0051] Example 2

[0052] The preparation process of an asphalt modifier for rutting-free pavement is as follows:

[0053] (1) First, weigh 400g of synthetic BR powder rubber, 100g of naphthenic oil, and 600g of bisphenol A type solid phenolic epoxy resin and put them into a mixer for stirring and oil filling. The mixing time is 5min. Then, add the mixture to a grinding disc-shaped mechanical chemical reactor and grind it repeatedly at room temperature. The heat during the grinding process is carried away by cooling water. The grinding is repeated 30 times to obtain mixture A.

[0054] (2) Weigh out 500g of octadecylamine, 200g of carbon black, 15g of sulfur, 10g of nonylphenol accelerator, 10g of antioxidant 1010, and 20g of UV-326 ultraviolet absorber respectively, add them to a high-speed mixer for mixing for 3 minutes, and then add them to a plastic grinding mill, controlling the grinding fineness to 40 mesh to obtain mixture B;

[0055] (3) Add the mixture A prepared in step (1) and the mixture B prepared in step (2) to a flat die granulator for granulation to prepare a rutting-free pavement asphalt modifier.

[0056] The method for preparing asphalt mixtures using the above-mentioned rutting-free pavement asphalt modifier:

[0057] S1. Use SMA-10 gradation for aggregate batching. The SBS modified asphalt needs to be heated to 170℃ and the aggregate needs to be heated to 210℃.

[0058] S2. Heat the mixing pot to 190℃, then add the stone material heated in S1 and the rutting-free pavement asphalt modifier and dry mix for 15 seconds. Mix until the rutting-free pavement asphalt modifier is completely melted and coated on the surface of the aggregate. The amount of rutting-free pavement asphalt modifier added is 2% of the aggregate.

[0059] S3. Add heated asphalt and mineral powder to the mixing pot in S2. Add SBS modified asphalt at an asphalt-aggregate ratio of 5.0%. Perform wet mixing and molding. The wet mixing time is 55s. Discharge the mixture to prepare a rutting-free asphalt mixture. Control the discharge temperature of the mixture to 200℃. Mold relevant mixture specimens at 185℃. Conduct mixture performance tests according to the requirements of the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 1.

[0060] Comparative Example 2

[0061] Using SMA-10 gradation and imported Japanese hot-mix epoxy resin, epoxy SMA-10 asphalt mixture was prepared. The preparation method is as follows:

[0062] S1. SBS modified asphalt needs to be heated to 160℃, and aggregate needs to be heated to 200℃;

[0063] S2. Heat the mixing pot to 180°C, then add the heated stone material from S1 and dry mix for 10 seconds;

[0064] S3. Add heated asphalt, mineral powder, and epoxy resin to the mixing pot in S2. Add SBS modified asphalt and Japanese hot-mix epoxy resin at an asphalt-aggregate ratio of 6.5%. The amount of hot-mix epoxy resin added is in accordance with the Japanese recommended amount (hot-mix epoxy: asphalt = 1:1), that is, the amount of hot-mix epoxy added is 3.25% of the aggregate. Wet mixing and molding are carried out, and the wet mixing time is 55s. The epoxy SMA-10 asphalt mixture is prepared by discharge. The discharge temperature of the mixture is controlled at 185℃. The relevant mixture specimens are molded at 175℃. The performance of the mixture is tested according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 1.

[0065] Comparative Example 3

[0066] Using SMA-10 gradation and SBS modified asphalt, without adding any admixtures, SMA-10 asphalt mixture was prepared. The preparation method is as follows:

[0067] S1. SBS modified asphalt needs to be heated to 160℃, and aggregate needs to be heated to 200℃;

[0068] S2. Heat the mixing pot to 180°C, then add the heated stone material from S1 and dry mix for 10 seconds;

[0069] S3. Add heated asphalt and mineral powder to the mixing pot in S2. Add SBS modified asphalt at an asphalt-aggregate ratio of 6.5% and wet mix and mold. The wet mixing time is 45s. Discharge the mixture to prepare ordinary SMA-10 asphalt mixture. Control the discharge temperature of the mixture to 175℃. Mold relevant mixture specimens at 165℃ and test the performance of the mixture according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 1.

[0070] Example 3

[0071] The preparation process of an asphalt modifier for rutting-free pavement is as follows:

[0072] (1) Weigh 350g of synthetic NBR powder rubber, 80g of paraffin oil, and 500g of bisphenol A type solid phenolic epoxy resin into a mixer and mix them with oil for 4 minutes. Then add the mixture to a grinding disc-shaped mechanical chemical reactor and grind it repeatedly at room temperature. Use cooling water to remove the heat during the grinding process. Grind it 20 times to obtain mixture A.

[0073] (2) Weigh 400g of octadecylamine, 180g of carbon black, 10g of sulfur, 8g of phenol accelerator, 8g of antioxidant 264, and 15g of UV-329 ultraviolet absorber respectively, add them to a high-speed mixer for mixing for 2 minutes, and then add them to a plastic grinding mill, controlling the grinding fineness to 30 mesh to obtain mixture B;

[0074] (3) Add the mixture A prepared in step (1) and the mixture B prepared in step (2) to a flat die granulator for granulation to prepare a rutting-free pavement asphalt modifier.

[0075] The method for preparing asphalt mixtures using the above-mentioned rutting-free pavement asphalt modifier:

[0076] S1. Use SUP-20 gradation for aggregate batching. The SBS modified asphalt needs to be heated to 160℃ and the aggregate needs to be heated to 210℃.

[0077] S2. Heat the mixing pot to 185°C, then add the stone material heated in S1 and the rutting-free pavement asphalt modifier and dry mix for 12 seconds. Mix until the rutting-free pavement asphalt modifier is completely melted and coated on the surface of the aggregate. The amount of rutting-free pavement asphalt modifier added is 1.2% of the aggregate.

[0078] S3. Add heated asphalt and mineral powder to the mixing pot in S2. The amount of base asphalt is added according to the asphalt-aggregate ratio of 4.0%. Wet mixing and molding are carried out. The wet mixing time is 50s. The mixture is discharged to prepare a rutting-free asphalt mixture. The discharge temperature of the mixture is controlled at 190℃. The relevant mixture specimens are molded at 180℃. The performance of the mixture is tested according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 2.

[0079] Comparative Example 4

[0080] Using SUP-20 gradation and selecting RA high-performance anti-rutting agent produced by the Highway Research Institute of the Ministry of Transport, anti-rutting SUP-20 asphalt mixture was prepared. The preparation method is as follows:

[0081] S1. SBS modified asphalt needs to be heated to 160℃, and aggregate needs to be heated to 200℃;

[0082] S2. Heat the mixing pot to 180°C, then add the stone material heated in S1 and the high-performance anti-rutting agent and dry mix for 15 seconds. Mix until the high-performance anti-rutting agent is completely melted and coated on the surface of the aggregate. The dosage of high-performance anti-rutting agent is 0.6% of the aggregate according to the manufacturer's recommended dosage.

[0083] S3. Add heated asphalt and mineral powder to the mixing pot in S2. The asphalt content is added according to the asphalt-aggregate ratio of 4.4%. Wet mixing and molding are carried out. The wet mixing time is 45s. The RA anti-rutting asphalt mixture is prepared by discharging. The discharge temperature of the mixture is controlled at 185℃. The relevant mixture specimens are molded at 175℃. The performance of the mixture is tested according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 2.

[0084] Example 4

[0085] The preparation process of an asphalt modifier for rutting-free pavement is as follows:

[0086] (1) Weigh 300g of synthetic SBR powder rubber, 50g of naphthenic oil, and 600g of bisphenol A type solid phenolic epoxy resin into a mixer and mix them with oil for 4 minutes. Then add the mixture to a grinding disc-shaped mechanical chemical reactor and grind it repeatedly at room temperature. Cool water is used to remove the heat during the grinding process. The grinding is repeated 25 times to obtain mixture A.

[0087] (2) Weigh out 450g of oleylamine, 150g of carbon black, 15g of sulfur, 10g of phenol accelerator, 10g of antioxidant 1010 and 20g of UV-326 ultraviolet absorber respectively, add them to a high-speed mixer for mixing for 3 minutes, and then add them to a plastic grinding mill, controlling the grinding fineness to 30 mesh to obtain mixture B;

[0088] (3) Add the mixture A prepared in step (1) and the mixture B prepared in step (2) to a flat die granulator for granulation to prepare a rutting-free pavement asphalt modifier.

[0089] The method for preparing asphalt mixtures using the above-mentioned rutting-free pavement asphalt modifier:

[0090] S1. Use EME-14 gradation for aggregate batching, and heat the base asphalt to 160℃ and the aggregate to 190℃.

[0091] S2. Heat the mixing pot to 180°C, then add the stone material heated in S1 and the rutting-free pavement asphalt modifier and dry mix for 10 seconds. Mix until the rutting-free pavement asphalt modifier is completely melted and coated on the surface of the aggregate. The amount of rutting-free pavement asphalt modifier added is 1.0% of the aggregate.

[0092] S3. Add heated asphalt and mineral powder to the mixing pot in S2. The amount of base asphalt is added according to the asphalt-aggregate ratio of 5.1%. Wet mixing and molding are carried out. The wet mixing time is 50s. The material is discharged to prepare a rutting-free asphalt mixture. The discharge temperature of the mixture is controlled at 185℃. The relevant mixture specimens are molded at 175℃. The performance of the mixture is tested according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 2.

[0093] Comparative Example 5

[0094] Using EME-14 gradation and selecting a composite high-modulus agent from Jiangsu Transportation Research Institute (Jiangsu Jiaotong University) with hard asphalt anti-rutting masterbatch as the main component, high-modulus EME-14 asphalt mixture was prepared. The preparation method is as follows:

[0095] S1. The base asphalt needs to be heated to 160℃, and the aggregate needs to be heated to 190℃;

[0096] S2. Heat the mixing pot to 180°C, then add the stone material heated in S1 and the composite high modulus agent and dry mix for 15 seconds. Mix until the composite high modulus agent is completely melted and coated on the surface of the aggregate. The high performance anti-rutting dosage is 1.0% of the mineral material according to the manufacturer's recommended dosage.

[0097] S3. Add heated asphalt and mineral powder to the mixing pot in S2. The asphalt content is added according to the asphalt-aggregate ratio of 4.4%. Wet mixing and molding are carried out. The wet mixing time is 50s. EME-14 asphalt mixture is prepared by discharge. The discharge temperature of the mixture is controlled at 185℃. The relevant mixture specimens are molded at 175℃. The performance of the mixture is tested according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 2.

[0098] Comparative Example 6

[0099] First, weigh out 300g of synthetic SBR powder rubber, 50g of naphthenic oil, 600g of bisphenol A type solid phenolic epoxy resin, 450g of oleylamine, 150g of carbon black, 15g of sulfur, 10g of phenol accelerator, 10g of antioxidant 1010, and 20g of UV-326 ultraviolet absorber, and add them to a high-speed mixer for mixing for 10 minutes to obtain a simple blended modifier.

[0100] The method for preparing asphalt mixtures using the above-mentioned direct and simple blending modifier has the following index scheme:

[0101] S1. The base asphalt needs to be heated to 160℃, and the aggregate needs to be heated to 190℃;

[0102] S2. Heat the mixing pot to 180°C, then add the stone material heated in S1 and the simple blending modifier and dry mix for 15 seconds. The recommended amount of the simple blending modifier is 1.0% of the mineral material.

[0103] S3. Add heated asphalt and mineral powder to the mixing pot in S2. The asphalt content is added according to the asphalt-aggregate ratio of 4.4%. Wet mixing and molding are carried out. The wet mixing time is 50s. EME-14 asphalt mixture is prepared by discharge. The discharge temperature of the mixture is controlled at 185℃. The relevant mixture specimens are molded at 175℃. The performance of the mixture is tested according to the requirements of the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The test results are shown in Table 2.

[0104] Table 1. Performance test results of asphalt mixtures in Examples 1, 2, Comparative Example 1, and Comparative Example 2.

[0105]

[0106] Table 2. Performance test results of asphalt mixtures in Examples 3-4 and Comparative Examples 4-6

[0107]

[0108] Tables 1 and 2 show the performance test results of the asphalt mixtures prepared in Examples 1-4 and Comparative Examples 1-6. Examples 1, 3, 4 and Comparative Examples 1, 3, 4, 5, 6 respectively compared the performance of asphalt mixtures using the rutting-free pavement asphalt modifier of the present invention, and French PR high modulus agent, high-performance anti-rutting agent, composite high modulus agent, conventional blank sample without admixtures, and asphalt mixtures using the proportion of the present invention after simple blending modification under AC-16, SUP-20, and EME-14 gradations. The data in the tables show that the dynamic stability of the mixture with the rutting-free pavement asphalt modifier of the present invention at 60℃ is greater than 50,000 cycles / mm, and the dynamic stability at 70℃ is 4.6 times, 7.0 times, and 5.0 times that of PR high modulus agent, high-performance anti-rutting agent, and composite high modulus agent, respectively, and 13.5 times that of the asphalt mixture without additives SMA-10. Furthermore, the Marshall stability of all mixtures is greater than 20 kN, indicating better high-temperature rutting resistance. From the perspective of the failure strain of small beams at -10℃, the failure strain of the asphalt mixture with the rutting-free pavement modifier of this invention is greater than 2500με, while the failure strain with the addition of high-performance anti-rutting agent and composite high modulus agent is less than 2000με. Therefore, the rutting-free asphalt mixture of this invention has better low-temperature crack resistance. In Example 2 and Comparative Example 2, using SMA-10 gradation, the performance of the rutting-free asphalt modified mixture of this invention and the imported Japanese hot-mix epoxy mixture were compared. The epoxy asphalt mixture performance test required curing at 60℃ for 4 days and then placing it at room temperature for 1 day before relevant tests.

[0109] Tables 1 and 2 also show that the Marshall strength of the rutting-free asphalt mixture reaches 45.8 kN, which is 63.2% of that of the epoxy asphalt mixture, and its dynamic stability at 70℃ is 77.7% of that of the epoxy asphalt mixture. This indicates that the high-temperature rutting resistance of the rutting-free asphalt mixture is slightly lower than that of the epoxy asphalt mixture, but it is much higher than that of asphalt mixtures with conventional anti-rutting agents and high modulus agents. Compared with epoxy asphalt mixtures, it has a better cost performance and does not require curing. In terms of low-temperature crack resistance, both it and epoxy asphalt mixtures have a value greater than 3500 με, and both have excellent low-temperature crack resistance.

[0110] As can be seen from Example 4 and Comparative Example 5 in Table 2, under the same material formulation as Example 4, Comparative Example 5 simply prepared a modifier after blending and used it directly. The properties of the asphalt mixture prepared by Comparative Example 5 were significantly reduced, and it could not achieve the effect of no rutting. Moreover, a large amount of unmelted modifier was present during mixing.

[0111] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A rutting-free asphalt modifier, characterized in that, It contains the following components, and the mass fractions of each component are as follows: 30-40 parts of synthetic powdered rubber, 40-60 parts of solid phenolic epoxy resin 5-10 parts of rubber filler oil, 30-50 parts of long-chain fatty amines 15-20 parts carbon black Sulfur 0.5-1.5 parts, Accelerator 0.5-1 part, Antioxidant 0.5-1 part, 1-2 parts of UV absorber; The synthetic powdered rubber is selected from any one of styrene-butadiene rubber, cis-butadiene rubber, and nitrile rubber; The rutting-free pavement asphalt modifier is obtained by mixing mixture A, which is obtained by blending and modifying synthetic powder rubber, rubber filler oil and solid phenolic epoxy resin using a special disc-shaped mechanical chemical reactor, with mixture B, which is obtained by grinding a mixture of long-chain fatty amine, carbon black, sulfur, accelerator, antioxidant and ultraviolet absorber using a plastic grinding mill.

2. The asphalt modifier for rutting-free pavement according to claim 1, characterized in that, The solid phenolic epoxy resin is a solid bisphenol A type phenolic epoxy resin; The rubber filler oil is selected from any one of aromatic oil, naphthenic oil, and paraffin oil; The long-chain fatty amine is selected from any one of hexadecylamine, octadecylamine, and oleylamine; The accelerator is a phenolic accelerator; The antioxidant is selected from any one of antioxidant BHT, antioxidant 1010, and antioxidant 264; The ultraviolet absorber is selected from any one of ultraviolet absorbers UV-531, UV-326, and UV-329.

3. The asphalt modifier for rutting-free pavement according to claim 2, characterized in that, The accelerator is selected from any one of 2,4,6-tris(dimethylaminomethyl)phenol, nonylphenol, and phenol.

4. A method for preparing a rutting-free pavement asphalt modifier according to any one of claims 1 to 3, characterized in that, The specific steps are as follows: (1) Weigh the synthetic powder rubber, rubber filler oil and solid phenolic epoxy resin according to the proportion, put them into the mixer and mix them with oil for 3 to 5 minutes. Then add the mixture to the grinding disc mechanical chemical reactor and grind it repeatedly at room temperature. The heat during the grinding process is carried away by cooling water. The grinding is repeated 10 to 30 times to obtain mixture A. (2) Add long-chain fatty amines, carbon black, sulfur, accelerators, antioxidants and ultraviolet absorbers to a high-speed mixer in proportion and mix for 2-3 minutes. Then add it to a plastic grinding mill and control the grinding fineness to 20-40 mesh to obtain mixture B. (3) Add the mixture A prepared in step (1) and the mixture B prepared in step (2) to a flat die granulator for granulation to prepare the rutting-free pavement asphalt modifier.

5. The application of the rutting-free pavement asphalt modifier according to any one of claims 1 to 3 in asphalt mixtures.

6. A method for preparing rutting-free asphalt mixture using the rutting-free pavement asphalt modifier according to any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Heat the asphalt and stone separately. Heat the stone to 190-220℃, and heat the asphalt to 150-160℃ when it is base asphalt and to 160-175℃ when it is SBS modified asphalt. (2) Heat the mixing pot to 180-190℃, then add the stone material heated in step (1) and the above-mentioned rutless pavement asphalt modifier and dry mix for 10-15 seconds. Mix until the rutless pavement asphalt modifier is completely melted and coated on the surface of the aggregate. (3) Add heated asphalt and mineral powder to the mixing pot in step (2), perform wet mixing and molding, the wet mixing time is 45-55s, and discharge to prepare rutting-free asphalt mixture. Control the discharge temperature of the mixture to 185-200℃. If it is below 175℃ or above 205℃, it is treated as waste. The molding temperature of the mixture is 175-185℃.

7. The method according to claim 6, characterized in that, The dosage of the rutting-free pavement asphalt modifier is 1.0-2.0% of the mass of the aggregate in the mixture, and the aggregate includes stone and mineral powder.

8. The method according to claim 6, characterized in that, The rutting-free asphalt mixture is applicable to AC, SMA, SUP, and EME dense-graded asphalt mixtures.

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